I didn't get any screen caps, but I was in a match earlier in my Grille where the final enemy tank (a KV) just vanished from sight. There was an M3 Lee and a Hetzer on either side of him, and he was moving around the two of them, but all of a sudden he vanished for about thirty seconds while my allies continued to shoot at him. He came back to my sight eventually, but there was still that frustrating period where I could not see a tank that was both well within range and definitely spotted by at least two allies.

This happens all the time and there are numerous topic posts about this issue. The spotting system in this game is rediculous but the devs have yet to do anything to fix it and continue to say that it is working as designed. Just one of the quirks we all have to contend with in this game. Keep in mind this game is still in Beta so flaws should be expected. We all hope that the devs will fix this eventually....